A kind of method of recovering ammonia from coking wastewater

Abstract

The present application discloses a method for recovering ammonia from coking wastewater, comprising: (1) introducing coking wastewater into a constant temperature tank, adding an appropriate amount of alkali to the coking wastewater to obtain coking wastewater A, and the temperature in the tank is 60-80° C. The pH of the waste water A is 10~13; (2) The coking waste water A is introduced into the stripping tower for ammonia recovery, the ammonia gas at the top of the tower enters the absorption tower, and the tower still obtains the coking waste water B; (3) The temperature of the coking waste water B is adjusted to 20 ~40℃, pH is 8~10, add an appropriate amount of modified expanded perlite adsorbent to coking wastewater B to remove the remaining ammonia; (4) backwash and regenerate the modified expanded perlite adsorbent, and continue to the next step. Ammonia removal; wherein, the modified expanded perlite adsorbent is the adsorbent obtained after sodium chloride modified expanded perlite. The method adopts a two-stage ammonia removal system, effectively removes ammonia in coking wastewater, reduces environmental pollution, and recycles most of the ammonia in coking wastewater, with low investment cost and high economic benefit.

Description

technical field [0001] The application relates to a method for recovering ammonia from coking wastewater, belonging to the technical field of wastewater treatment. Background technique [0002] The source of coking wastewater is relatively complex, and it is the wastewater produced in the high-temperature dry distillation of raw coal, the refining process of chemical products and the gas purification process. It is mainly composed of condensed water (wet water on the surface of coal, combined water in raw coal and water vapor attached to raw materials mixed in the process of processing and production and formed by cooling when it is drawn out of the coke oven), remaining ammonia water (accounting for more than half of the total waste water) ), coke quenching sewage, product separation water, waste acid and waste alkali liquor produced in the process of refining products and other production waste water and domestic sewage are collected together. Residual ammonia water is th...

AI Technical Summary

Problems solved by technology

The indirect ammonia distillation method mainly includes the heat conduction oil heating method and the tube furnace heating method, but the process is relatively complicated, the one-time construction investment is large, and the safety requirements for the process and equipment are high.

Images